Therapeutic Potential of Milk Whey
4. Therapeutic Properties of Milk Whey 1. Antimicrobial
3.9. Proteose Peptone Component 3 (PP3)
These are those proteins that are left in solution after the milk is heated at high temperature followed by its acidification up to pH 4.7.
The proteose peptone 3 component is found only in whey excluding from the human source. It is produced during the fermentation of fat-free bovine milk and enhances the production of monoclonal antibodies by human hybridoma cells (Krissansen, 2007 [33]).
4. Therapeutic Properties of Milk Whey
Beverages 2017, 3, 31
4.2. Anti-Cancerous
Some cheese whey components possess anticancer properties. The sulphur-containing amino-acids including cysteine and methionine, are found in good amounts in whey protein. Cysteine and methionine are utilized in glutathione synthesis. Glutathione is a substrate for two classes of enzymes that catalyze detoxification compounds and bind mutagens and carcinogens, thus facilitating their elimination from the body. The ability of lactoferrinto bind iron is another added advantage in the prevention of colon cancer. They induce apoptosis in tumour cells and so are useful adjunct in colon cancer therapy.
Sphingomyelin, one of the most abundant whey-derived sphingolipids, have potential to inhibit colon cancer. Sphingomyelins also regulate growth factor receptors, such as the transforming growth factor beta family (TGF-β).
TGF-βs are a multifunctional family of growth factors that regulate cell growth in normal and tumour cells by suppressing proliferation, inducing differentiation and apoptosis. TGF-β passes out unaffected through the stomach and maintains bioactivity in colon by withstanding enzymatic proteolysis.
Several scientific studies, based on experiments on animal experiments have shown the therapeutic effect of bovine lactoferrin (BLF) in treating distinct types of cancer (Gill & Cross, 2000 [41]), including colon cancer (Masuda et al., 2000 [42]). Besides this, the iron-binding capacity of bovine lactoferrin is responsible for its anticancer activity. The proposed mechanisms are that free iron act as a mutagenic promoter, by inducing oxidative damage to the nucleic acid structure; hence, when bovine lactoferrin binds iron in tissues, it reduces the risk of oxidant-induced carcinomas and colon adenocarcinomas. Studies are also available that pertain to such other cancers as lung, bladder, tongue and oesophagus, and which convey similar results (Masuda et al., 2000; Tanaka et al., 2000 [42,43]).
4.3. Immune-Enhancer
IgGs, Lp and Lf concentrated from whey participates in host immunity. IgGs binds with bacterial toxins and lowers the bacterial load in the large bowel. Dietary Lp and Lf plays a vital role in host immunity through their antibacterial action on pathogenic microorganisms. Thus, supplementing diets with whey-derived adjuncts shifts the balance of intestinal microflora and aids in immune enhancement. Calcium, by virtue of its probiotic activity and influence on macrophages, neutrophils and other white blood cell (WBC) subtypes are also classified as immune-modifying minerals.
Lf provides immune modulation as it is a natural component of the human immune system and is found in the body’s mucous substances including saliva.
TGFs are abundant in milk (1–2 mg/L) and colostrum (20–40 mg/L) and serve a major role in GI integrity of newborn animals.
TGF-beta2 resides locally near the top of the intestinal villi, and inhibits the proliferation and signaling neutrophils as a part of innate host immunity.
Bovine lactoferrin upon stimulation of the immune system increases macrophage activity, causes induction of inflammatory cytokines, including IL-8, TNF-a and nitric oxide, stimulates proliferation of lymphocytes, and activates monocytes, natural killer (NK) cells and neutrophils (Gahr et al., 1991 [44]).
4.4. Prebiotic Properties
There are some whey-derived carbohydrate components that possess prebiotic activity. Lactose support LAB (such as Bifidobacteria & Lactobacilli). Stallic acids (type of oligosaccharides that are commonly found in whey), are typically attached to proteins that have been shown to possess prebiotic properties. Besides, three other non-carbohydrate prebiotics from whey are a protein called glycomacropeptide (GMP) that is derived from the partial enzymatic breakdown of kappa-casein during cheese production that supports the growth of bifidobacteria; second is lactoferrin (Lf), which supports the growth of bifidobacteria and lactobacilli and third component with prebiotic potential
124
is mineral, calcium in form of calcium phosphate. It selectively stimulates the growth of intestinal lactobacilli and decreases the severity of Salmonella infections in rats (Kassem et al., 2015 [45]).
4.5. Anti-Inflammatory Properties
The role of whey proteins on hypertension is due to its effect on inflammation and Renin-Angiotensin System (RAS). The Angiotensin-Converting Enzyme (ACE) inhibitors possess anti-inflammatory properties (Sousa et al., 2012 [46]). In a study it was found that the consumption of whey proteins depleted the plasma levels of pro-inflammatory cytokines (IL-1 beta: 59% and IL-6: 29%) as compared to the consumption of same amount of casein. Thus, reduction of pro-inflammatory cytokines can also be associated with weight loss after consumption of whey proteins and its amino acids (Luhovyy et al., 2007 [47]).
4.6. Cardiovascular and Related Diseases
Cardiovascular disease (CVD) is associated with number of factors such as age, genetic constitution, obesity, sedentary lifestyle and alcohol intake and quality of dietary fat. Milk contains more than 12 different types of fat, including sphingolipids, free sterols, cholesterol and oleic acid.
Several studies have shown that intake of milk and dairy products lower blood pressure and reduce the risk of hypertension (Groziak and Miller, 2000 [48]).
A study was undertaken to investigate the effect of fermented milk (Lactobacillus casei and Streptococcus thermophiles) supplement with an added whey protein concentrate on serum lipids and blood pressure on a group of 20 healthy adult males (Kawase et al., 2000 [49]). During the course of eight weeks, volunteers consumed 200 mL of fermented milk with whey protein concentrate or a placebo in the morning and evening. The placebo consisted of a non-fermented milk product without the addition of whey protein concentrate. After eight weeks, the fermented-milk group showed significantly higher High Density Lipoproteins (HDLs) and lower triglycerides and systolic blood pressure than did the placebo group.
In yet another study, the aim was to investigate the acute effects of dietary whey proteins on lipids, glucose and insulin, and resting energy expenditure in overweight and obese post-menopausal women, a population that is highly susceptible to cardiovascular disease. The findings suggested that a single dose of whey protein can decrease arterial exposure to smaller triglycerides-enriched lipoprotein particles compared to the glucose and casein meals in the postprandial period in overweight and obese, post-menopausal women (Pal et al., 2010 [50]).
4.7. GastroIntestinal Health
Whey proteins exert a therapeutic effect on the gastric mucosa. This effect is due to the presence of sulfhydryl group in aminoacid cysteine and its linkage with glutamic acid in the production of glutathione.
In a research by Rosaneli et al. [51], it was observed that when rats showed a 41% reduction in ulcerative lesions caused by ethanol ingestion when they were fed a whey protein concentrate, while a 73% reduction rate was observed following repeat doses of whey (McGregor and Poppitt, 2013 [52]).
Whey proteins are absorbed faster in body than casein. The lower absorption rate of casein in its native micellar form is due to the low pH conditions in the stomach that cause casein clotting and delays gastric emptying (Dangin et al., 2001 [53]). Therefore, plasma amino acids are more rapidly elevated following whey proteins consumption; whereas changes in plasma amino acids are lower and more sustained following micellar casein consumption. Thus, processing of whey proteins or casein fractions through hydrolysis can markedly influence absorption and subsequent plasma amino acid profiles.
Beverages 2017, 3, 31
4.8. Physical Strength and Performance for Athletes
Several studies have shown that whey proteins have tremendous nutraceutical potential for athletes. They are often referred to as ‘gold standard’ or ‘fast protein’ for their unique ability to provide nourishment to muscles. This is due to several factors such as their solubility, easily digestible, efficient absorption. They contain all the essential amino acids required in daily diet and have an ideal combination of amino acids to help to improve body composition and enhance athletic performance.
Whey protein is a rich source of branched chain amino acids that are important for athletes since they are metabolized directly into muscle tissue and repair and rebuild lean muscle tissue. Whey protein is an excellent source of leucine (an essential amino acid) that plays a key role in promoting muscle protein synthesis and muscle growth in athletes. It has been reported that whey protein isolate has approximately 50% more leucine than soy protein isolate. Whey protein increases the level of glutathione in the body and helps to maintain a healthy immune system (Gupta et al., 2012 [4]).
4.9. Obesity Control
Numerous studies have proved that whey proteins help in weight management and obesity control. The mechanism involved is through the influence of whey proteins on the hormones that controls appetite and hunger (Hall et al., 2003 [54]). Consumption of a high-protein diet has a greater satiety thereby reducing energy intake and subsequent adiposity. It has been found that whey proteins are even more effective than red meat in reducing weight gain and also increases insulin sensitivity of the body. The other proposed mode of action is that diet rich inα-lactalbumin enhances the lipid oxidation and rapidly delivers amino acids for use during exercise, thereby decreasing adiposity (Bouthegourd et al., 2002 [55]). Calcium is also known to influence energy metabolism as it regulates adipocyte lipid metabolism and triglyceride storage. This has been experimentally supported by Zemel 2002 [56] who demonstrated a greater effect of dairy versus non-dairy sources of calcium for improving body composition.
4.10. Protection against Human Immunodeficiency Virus (HIV)
Research has shown that individuals infected with HIV exhibit glutathione deficiency.
Supplementation of whey elevates the levels of glutathione (GSH) and helps in increasing the immune defense mechanism of the host.
A research was undertaken by Micke et al. [57] on 30 subjects infected with HIV. They were randomized and received a daily dose of 45 g whey proteins from one of two sources Protectamin®or Immunocal. These two products are commercially available and possess different amino acid profiles.
The oral supplementation was given for two weeks. After two weeks, the Protectamin-supplemented group demonstrated significantly elevated glutathione levels while the Immunocal group had statistically non-significant elevations. These results clearly showed that high levels of glutathione supplementation provide protection against HIV.
4.11. Diabetes
Numerous studies have proved that whey proteins help to control the blood glucose levels and provide additional benefits for weight management. This is a main concern for type-2 diabetics (Shankar and Bansal, 2013 [58]). Whey proteins are thus high biological, high-quality and value protein suitable for diabetic patients. Ingestion of whey proteins leads to more rapid secretion of insulin than micellar casein (McGregor and Poppitt, 2013 [52]).
4.12. Appetite Suppression
It has been mentioned earlier that whey based beverages regulates body weight and helps in controlling obesity. This is due to some amino acids liberated from whey proteins during in vivo digestion that also stimulate the release of hormones including insulin. Its secretion directly affects
126
food intake regulation by modifying glycemic response and suppressing appetite and, consequently reduces body weight... Some other hormones are also involved in appetite suppression either directly in the hypothalamus, such as ghrelin, or indirectly through the vagal nerve, such as cholecystokinin (CCK) and Peptide YY (PYY) (Jakubowicz and Froy, 2013 [59]). Glyco-macropeptide is a powerful stimulator of CCK, which is an appetite-suppressing hormone that plays essential roles related to gastrointestinal function; including the regulation of food intake. Further research is required to study the effects of GMP and CCK as an appetite suppressant (Walzem, 1999 [60]).
4.13. Ageing
Numerous studies have shown that whey protein based drinks play an important role in delaying the ageing process. During ageing, there is a continuous but slow degeneration of skeletal muscle mass (sarcopenia). In elderly population the skeletal muscle mass is completely impaired and inhibited.
Whey proteins are a rich source of essential amino acids that contributes to its anabolic properties.
There is an increase in availability of postprandial plasma amino acids that stimulates synthesis of muscle proteins (Pennings et al., 2011 [61]). Whey proteins contain glutathione that is an important antioxidant involved in the maintenance of functional and structural integrity of muscular tissue undergoing oxidative damage during exercise and aging.
4.14. Wound Healing
Wound healing involves the growth of new skin through the use of proteins and their amino acids. Healing process is delayed when there are inadequate amounts of protein or diets high in poor-quality proteins, such as gelatin are present. Whey proteins comprises of good quality proteins and are therefore often recommended by physicians after any surgery or burn therapy (Gupta et al., 2012 [4]).